Cationic isoquinoline pesticide



Patented Feb. 3, 1948.

UNITED STATES PATENT OFFICE 2,435,451; ca'rromc Isoonmonma rss'rrcmaHugh H. Masher, Teaneck, N. 1., and Frank L.

- Howard, Kingston, 8.1.,

auignorstoOnyxOil & Chemical Company, a corporation of Dela- No Drawing.Application December 9, 1943,, Serial No. maze in which R1 is an alkylgroup of 8 to 18 carbon atoms; R: is an acid radical (say a halide); andRe represents one or more alkyl groups (of 1 to 4 carbon atoms) orhydroxyl groups in the a, p, 7, 1, 2, 8, or 4 positions.

The compounds used in the process of our invention may be prepared verysimply by reacting isoquinoline or an isoquinoline derivative containingthe R: radicals with an appropriate alkyl halide. Thus isoquinoline maybe reacted with lauryl chloride in the absence of water at 120 to 130 C.over a two hour period. Likewise, isoquinoline may be reacted with cetylbromide under similar conditions. The product of the first reaction islauryl isoquinolinium chloride; that of the second is cetylisoquinolinium bromide. Both are colorless to light amber liquids whichare soluble in many organic solvents including acetone and certainglycol ethers such as the Cellosolves and Carbitol of Carbide and CarbonChemical Corporation, for example, the mono ethyl ether of diethyleneglycol. The compounds are insoluble in ether and in many hydrocarbons,including gasoline and naphtha. They are quite soluble in hot water andmoderately soluble in cold. Clear cold solutions of the compounds can beprepared with coupling agents including acetone, Cellosolves andCarbitol."

The compounds used in the process are surface active and cationic innature and have good wetting, penetrating and emulsifying properties.Aqueous solutions containing the compounds foam vigorously and all ofthe compounds exert a marked detergent action.

The compounds used have marked antiseptic properties and are toxic tobacteria and myccpbyta. as well as to other micro-flora and micro-iauna.

The compounds are particularly useful in protecting higher plantsagainst the action of pests.

for their toxic character with respect to microflora and micro-fauna,their high detergency, and their cationic nature make them'excellent forthe treatment of the organs of higher plants to prevent the attack ofbacteria, fungi, etc.

The fungicidal action of two of the compounds are shown in the followingTable I, which is a summary of a fungous spore dosage responsegermination test.

Table 1.Poteuiiul fungicidal value using macrosporium sarcinaefm-mespores on cellulose nitrute surface rao'rao'raN'r ACTION Treatment .001%.0005% M259}, .0001? Lsnryl isoquinolinium brom 96 68 40 10 Cetyliaoqninolininm bromide 96 33 26 I 1 Mean per cent inhibitionconcentration.

The compounds are particularly useful as plant sprays, for they aresubstantially colorless (or at most very slightly colored), whereasnormal quinolinium compounds are highly coloredusually bright red.Moreover, the compounds can be used in relatively high concentrations onplant foliage without producing substantial injury. This is shown by thefollowing:

Table II.-Phyt0to:cicity of isoquinolinium c m pounds on succulentgreenhouse tomato foliage. The average per cent of leaf area killedbyincreasing concentrations of the tomicant is shown when a dip methodwas used For use in plant treatment of said plants, the compounds shouldnot be used at concentrations greater than one part in 2000, because oftheir phytotoxicity at higher concentrations. However, they need not beused at concentrations even as high as one in 2000. for they areremarksbly efl'ective in the destruction of bacteria and fulngi at lowerconcentrations, say as low as one part in 100,000.

We claim: v

1. In the treatment of higher plants to protect them against the actionoi pests and fungi, etc., the improvement which comprises applying toorgans or the plants a cationic iaoquinolinium compound having attachedto its nitrogen an acid radical and a streisht chain hydrocarbon radicalcontaining 8 to 18 carbon atoms.

2. In the treatment of higher plants to protect them against the actionof pests and t'ungi, etc.,

the improvement which comprises applying to 15 to organs of the plants acationic isoquinolinium g5 compound having attached to its nitrogen anacid radical and an alkyl radical containing 8 to 18 carbon atoms.

4. In the treatment or higher plants to protect them against the actionof pests. fungi, etc.. the improvement which comprises applying toorgans oi! the plants a cationic isoquinolinium compound 3 havingattached to its nitrogen an acid radical and an alkyl radical containing8 to 18 carbon atoms. the concentration oi the compound in the solutionbeing from 1:2000 to 1:100,000.

HUGH H. MOM-ER. FRANK L. HOWARD.

, nnranhncns crrnn The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,295,60 Shelton Sept. 8, 19422,075,859 Salzberg Mar. 80, 1937 20 2,292,423 Yohe Aug. 11, 1942 478,495Ziegler July 5, 1892 1,808,563 Prill May 19, 1981 505,1t1 Taueh Sept.19. 1893 FOREIGN PATENTS Number Country Date 18,516 meat Britain 1884

